Communication System

1. A communication system comprising a host vehicle and a server, wherein: the host vehicle includes: a camera; a first processor; a variable directional antenna; and a transmitter, and the server includes: a second processor; and a memory the camera is configured to acquire an image of a road as road information; the memory stores relationship information that associates types of the road information with transmission directions of the road information in advance; the second processors is configured to: acquire the road information from the host vehicle; identify a type of the road information based on the image included in the road information; identify a transmission direction of the road information from the host vehicle, based on the identified type of the road information and the relationship information stored in the memory; and determine whether a reception device is present in the identified transmission direction, based on vehicular equipment information about presence or absence of the reception device and vehicular position information transmitted from each of a plurality of vehicles other than the host vehicle, and wherein the first processor is configured to: acquire information about the transmission direction from the server; and utilize the transmitter and the variable directional antenna to transmit the road information in the transmission direction when the second processor determines that the reception device is present in the transmission direction.

2. The communication system according to claim 1 , wherein the second processor is configured to detect a time period during which communication with the reception device is enabled, and wherein the first processor controls the transmitter to transmit the road information at the time period detected by the second processor.

3. The communication system according to claim 1 , wherein the plurality of vehicles transmit to the server probe information including the vehicular position information and the vehicular equipment information.